The bed that enables height-adjusting operations such as back-raising and leg-raising is basically configured such that the bottom is divided into a plurality of sections, e.g., a back bottom, a hip bottom, a leg bottom and a foot bottom to make these sections capable of flexing by joining one section to another in a mutually flexing manner, or by pivotally supporting part of the sections on the frame that supports the bottom.
However, if, for example, the back bottom and the hip bottom are merely configured so as to rotate on their pivots to realize a flexed profile, the mattress rested on the bottom is compressed by the back bottom and hip bottom. As a result, there has been a problem that the bed user such as a patient or the like lying in the supine position feels pressure or other discomfort around the belly. In order to eliminate problems of this kind, measures have been conventionally considered.
The applicant of the invention hereof also has proposed various bottom structures that enable the flexing portion between the back bottom and the hip bottom to curve with a suitable curvature and fit to the flexed posture of the user's body. Japanese Patent Application Laid-open H11-89886 is one example of the proposals of the applicant hereof.
FIG. 9 is an external perspective view showing one example of a bed having such a flexing bottom. FIG. 10 is an external perspective view showing a flexing bottom used in this bed. As shown in FIG. 9, a flexing bottom 102 in a bed 100 is arranged between a back bottom 101 and a hip bottom 103. The flexing bottom 102 is coupled at one end with the back bottom 101 and at the other end with the hip bottom 103. As shown in FIG. 10, the flexing bottom 102 is comprised of a plurality of strip-like members 113 connected in series, each member can create an appropriate angle of flexure with adjacent member to form a suitable curving shape as a whole.
In the flexing bottom 102, each strip-like member 113 is formed with a plurality of stopper pieces 114 each having a hook-shaped part and a plurality of guide pieces 115 arranged appropriately apart from, and in parallel with, the stopper piece 114, across the one longitudinal side of the strip-like member 113. Further, on the opposite longitudinal side of the strip-like member 113, indentations for receiving the stopper pieces 114 and guide pieces 115 of the adjacent strip-like member 113 to be coupled are formed. These indentations are configured so that the size of the indentation is slightly greater than that of stopper piece 114 and guide piece 115. Further, at either end face of the strip-like member 113 in the bed width direction, a tongue 118 is integrally and protectively formed in parallel with the stopper piece 114 that is located near the end face. This tongue 118 is to prevent fingers and other objects from entering the space between neighboring strip-like members 113 from the end face side of the strip-like member 113 in the bed width direction. The tongues 118 are configured so that the tongue 118 of one strip-like member 113 receives at its proximal end the thrust from the distal end of the tongue 118 of the adjacent strip-like member 113 when the latter or adjacent strip-like member 113 sinks its stopper pieces 114 and guide pieces 115 into the indentations of the former strip-like member 113.
When a height-adjusting operation is performed in abed 100 (see FIG. 9) to which the above-described flexing bottom 102 is applied, the strip-like members 113 can shift little by little from each other to curve the flexing bottom 102 located from the position below the back to the position below the hips, in a downward convex form with an appropriate curvature over the entire flexing bottom 102, as shown in FIG. 10.